Interesting question, but a tough one to answer. I'll give this a try. I haven’t included goalies. For fun, I’ve included a modern comparison so people who don’t know much about hockey history can get a sense of who the player is like.
1) Eddie Shore. Shore was arguably the second-best defenseman of all time. He led all defensemen in scoring 5 times, played excellent defense, and was one of the toughest & meanest players ever. His combination of skill (as demonstrated by end-to-end rushes and great passing) and toughness (fights, playing through injuries, trekking through a dangerous snowstorm to make it to a game on time and then playing all 60 minutes) is matched by only a few players before or after. Shore won the Hart trophy four times and probably would have won 5-8 Norris trophies had they been around back then. (Modern comparison: Lidstrom’s offense and consistency with Foote’s toughness and defensive skill)
2) Howie Morenz. One of the most dominant players of all time. Led the league in scoring twice and won three Hart trophies. Five 100-pt seasons adjusted for era. Extraordinary level of skill in terms of skating and stickhandling abilities. Equally adept at scoring and setting up teammates. By all accounts, Morenz was a great defensive player as well who knew the value of playing on both sides of the ice. It’s a toss-up between Shore and Morenz for first. (Modern comparison: probably closest to Joe Sakic or Mike Modano, except even more dominant)
3) Bill Cook. Cook was the ultimate power forward before the term even existed. He spent four years dominating the WCHL before dominating the NHL for the next decade. In four years in the WCHL, Cook led the league in goals twice and led the league in scoring tree years in a row. When he came to the NHL, Cook led the league in goals twice (runner-up twice) and led the league in scoring twice. Adjusted for era Cook had five 50 goal seasons and four 100 point seasons. However, Cook was more important than just offense. He was big and tough for his day and could, by all accounts, change a game with a single hit. Cook was twice runner-up for the Hart. (Modern comparison: maybe Brendan Shanahan from a few years ago)
4) Nels Stewart. Another dominant power forward, Stewart won two Hart trophies and led the league in scoring once. Like Cook, Stewart was a power forward who used his size and strength to drive through opponents. Stewart may have only won the Art Ross once, but he was supremely consistent, finishing in the top ten in scoring 10 times in 13 years. Stewart also led the league in goals twice. Stewart was an excellent defensive player. In his rookie season, his team’s star defenseman Dunc Monro was injured during the playoffs. Stewart, due to his defensive excellence, filled in on the blueline and helped lead the Maroons to a Stanley Cup victory. He still managed to score an amazing 6 of his team’s 10 goals. (Modern comparison: Forsberg, except healthier and more of a goal-scorer).
5) King Clancy. Clancy was an excellent combination of speed and toughness. He was an extremely fast skater and engaged in numerous end-to-end rushes. These skills allowed him to lead all defensemen in scoring three times. Clancy was small for his era, but was aggressive and tough. He was willing to check and battle with anybody. He likely would have won several Norris trophies had they been around back then. (Modern comparison: a much more physical version of Sergei Zubov).
6) Earl Seibert. This is a surprise pick, but I think Seibert may be the most underrated player in NHL history. Seibert was an all-star ten years in a row. The only other defensemen who can claim that honour are Harvey and Bourque. Seibert was one of the main reasons the awful Blackhawks won the Cup in 1938, scoring 7 points in 10 games, a level of offense that was unheard of at that time for a defenseman. Notwithstanding the 1938 playoffs, Seibert wasn’t very good offensively, but he used his enormous size and strength to neutralize opponents. (Modern comparison: Zdeno Chara)
7) Syl Apps Senior. It must have been tough for Syl Apps to come so close to so many awards, but to never win. Apps was runner-up for the Hart three times and came in third-place twice. He was also runner-up for the Art Ross trophy three times. Still, he does have some impressive hardware, including 5 all-star selections, the Calder, and he led the league in assists twice. More importantly, Apps was a strong playoff performer and helped lead the Leafs to the Stanley Cup in 1942 after they started the final against Detroit in a 3-0 deficit. To this day it remains one of the most stunning playoff comebacks in sports history. Apps also has a reputation as one of the classiest and cleanest players ever to play. (Modern comparison: Steve Yzerman around 1996-8).
8) Cy Denneny. One of the most dominant offensive players of any era, Denneny was a perennial threat for the Art Ross. He led the league in scoring only once, but was runner-up five times. Denneny had some explosive years, including five years with 40+ adjusted goals and two years with 130+ adjusted points. Ironically, Denneny started his career as a goon, designated to protect teammates. When Denneny became a scorer, he used his size and strength to defend himself. In his last season (as player/coach) he led the Bruins to win the Stanley Cup. (Modern comparison: maybe Jagr due to his offensive dominance, but their styles are completely different).
9) Frank Boucher. Boucher was easily one of the most dominant playmakers in hockey history. He bounced between the NHL, PCHA and WCHL before hitting his stride in the NHL in 1927. Boucher led the league in assists three times and was runner up four times. His brilliant playmaking and on-ice communications helped teammates reach career-highs in goals and points. Boucher by all accounts was a great defensive player and almost never took penalties. Five straight years with 100+ adjusted points. He later went on to become one of the NHL’s most brilliant coaches. (Modern comparison: Adam Oates).
10) Charlie Conacher. The third power forward on the list. He was more dominant than either Cook or Stewart, but severely lacks longevity. He was only an elite player for six years, but those years were extremely impressive. Conacher led the NHL in goals five times, the same number as Gretzky, Lemieux, Howe, Richard, etc. Only Bobby Hull and Esposito have done it more. Conacher was a five-time all-star and led the league in scoring twice. His slapshot was reportedly so hard, it would dent the boards. Conacher was a gentle giant, who was generally calm and never fought. Nonetheless, he used his size and incredible strength to go through (not around) opponents. Conacher reportedly was one of the best stickhanlders of his era, though he was also quite fond of simply crashing the net and knocking opposing goalies over. (Modern comparison: maybe Todd Bertuzzi, but Conacher wasn’t nearly as aggressive).
Notable omissions and close calls:
- Cyclone Taylor. Incredibly dominant, but never played a game in the NHL. Also, it’s hard to determine how much he accomplished as a forward and how much was as a rover. Too many uncertainties, so I left him out.
- Ted Kennedy. I left him out because most of his career, including his Hart, extended beyond 1950. But he deserves mention for this: the Hockey Hall of Fame awarded him Conn Smythe trophies for 1945, 1947 and 1948.
- Joe Malone. Led the NHL in scoring twice and led the NHA once. However, he didn’t produce long enough in the NHL at a high level.
- Aurel Joliat. Very hard to leave out. Won a Hart and was a four-time all-star. Two 100+ pt seasons and four more 80+ pt seasons. Excellent defense and checking. Similar to Forsberg.
- Bill Cowley. Two Hart trophies, 5-time all-star, 1 Art Ross. Great player, there just wasn’t room in the top ten.
- Newsy Lalonde. Led the NHL in scoring twice and was runner-up once. Routinely in the top ten scorers, regardless of what league he played in. I thought he was worth mentioning.
- Harry Cameron. Was a top-5 scorer three times. Played in an era when there was no Hart trophies, no Norris trophies and no all-star teams, so it’s very hard to judge how good he was. Still, if nothing else, it’s clear that Cameron was very dominant offensively.
- Eddie Gerard. I left him off because he only played 6 years in the NHL and I don’t think he dominated any more than Shore, Clancy, Seibert, Cameron or Patrick, who were more dominant, around longer, or both.
- Joe Primeau. Led the league in assists four times.
- Harvey Busher Jackson. Had some high-scoring seasons. Five-time all-star.
- Dit Clapper. Not the most dominant player, but the first to play for 20 years. Versatile (was used as both a forward and a defenseman).
- Milt Schmidt. Half his career and accomplishments. was after 1950.
- Lester Patrick. I won’t lie, I simply forgot about him earlier. Excellent offense and creativity.
Hopefully this was interesting. I’m definitely interested in hearing what others think.